That number will not do you any good with grass seed especially if its bluegrass
seed since they are so small. Broadcast Spreaders are usually calibrated for
granular particulates.

If I was you (I'm not, I hired the local illegals to oversee my lawn):
I would break my lawn into 1000sqft or some multiple sections and put in 2 1/2
pounds of seed per 1000sqft and then put the spreader on a low setting and then
over seed making sure you have uniform coverage.

Rolling Thunder wrote:

I am over seeding a tall fescue lawn with Carolina Blend tall fescue.
The bag doesn't specify the spreader's setting. For over seeding,
it appears the amount is 2 1/2 lbs. per 1,000 sq ft. The spreader
is a Scotts Speedy 3000 (rotary type). What is the spreader
setting?

Thunder

P.S. I've aerated and fertilized and am ready for the over seeding.